Dag Nasty is an American punk rock band that formed in Washington D.C. in 1985. The band is a significant figure in the development of the post-hardcore and melodic hardcore genres, emerging from the same hardcore punk scene that gave rise to bands like Minor Threat and Bad Brains. The original lineup consisted of Brian Baker (formerly of Minor Threat, who would later join Bad Religion), Shawn Brown (later replaced by Dave Smalley), Roger Marbury, and Colin Sears. Dag Nasty's sound is distinguished by their melodic approach to hardcore music, combining introspective lyrics and complex guitar work that strayed from the genre's typically blunt-force aggression.

Throughout its fluctuating history, the band has released several albums and undergone multiple lineup changes while maintaining a dedicated fan base. Key releases include their influential debut "Can I Say" (1986) and the follow-up "Wig Out at Denko's" (1987), both of which showcased the band's ability to blend emotive lyrical themes with a more refined hardcore sound. Despite disbanding and reuniting multiple times, Dag Nasty's influence has persisted, with the 2002 album "Minority of One" marking a return to their roots and showcasing their lasting appeal. In 2010, they issued "Dag With Shawn," which featured early recordings with original vocalist Shawn Brown. The single "Cold Heart" released in 2016, displayed the band's ongoing energy and commitment to their craft, even three decades after their formation. Dag Nasty remains a touchstone for fans of punk's evolution, with their heartfelt approach to songwriting and a commitment to musical innovation.